Combined automatic and manual



L. P. HUTT COMBINED AUTOMATIC AND MANUAL CIRCUIT CONTROL DEVICES Jan.23, 1934.

Original Filed Feb. 28, 1930 I'hve'ncor: Leonord I? Hubb, by M PatentedJan. 23, 1934 PATENT OFFICE COMBINED AUTOMATIC AND MANUALCIRCUIT-CONTROL DEVICES Leonard P. Hutt, Schenectady, N. Y., assignor toGeneral Electric Company, a corporation of New York Original applicationFebruary 28, 1930, Serial Nay 432,204. Divided and this applicationAugust 5, 1932. Serial No. 627,590

7 Claims. (01. 62-4) My invention relates to circuit controllingdevices, particularly circuit-controlling devices for controllingelectrically operated apparatus, such as domestic electric refrigeratorsorthe like.

This application is a division of my copending application, Serial No.432,204, filed February 28, 1930, and assigned to the same assignee asthe present invention.

In refrigerator controlling devices of the char acter set forth, inorder to avoid a prolonged shutdown of the refrigerator in case of someslight failure of the control device, it is desirable that it be capableof being quickly replaced by another unit.

It is also desirable thatsuch replacement be made without the necessityof taking apart any of the control mechanism or of disconnecting andreconnecting wires with the possibility'of making wrong connections inputting in a new control device. Appearance and safety require that anymeans for instantly connecting the control device to render it operativebe concealed and at the same time permit quick replacement. Anarrangement having these desirable features will not only save time butwill insure proper operation of the apparatus controlled after a newunit has been put in to replace the defective unit.

Hence, it is a general object of my invention to provide an improvedrefrigerator control having the advantageous features noted above.

More specifically, it is an object of my invention to provide asub-panel connection means permitting said control device to be quicklyre moved from and connected to the sub-panel to control the refrigeratorcircuit, said connection permitting the device to be quickly replaced bya new control device in case of failure.

It is a further object of my invention to provide a connection means forthe control device which will eliminate the necessity of disconnectingand reconnecting the wires'to the control or the connecting means.

Another object of my invention is to provide a connecting means which isconcealed for the sake of appearance and safety and in whichnevertheless quick replacement of a defective unit by anew unit ispossible.

Other objects will appear hereinafter.

In the preferred embodiment of my invention I provide an automaticswitch means responsive to different predetermined temperatures. Itconsists of an overcenter snap switch operated by means of atemperature-responsive device. A resilient means under compressionopposes the temperature-responsive device and the compression of thisresilient means may be varied to change the temperatures to which theswitch will respond. A member biased to open the switch is normally heldagainst its bias by means of a heat responsive device which responds tooverload conditions to release the biased member to open the switch. Amanual control means is provided for releasing the biased member fromthe control of the heat responsive device and for placing the biasedmember under the control of the heat responsive device thus manuallycontrolling the switch. The switch mechanism is provided with a coverthrough which the adjusting means for the resilient means opposing thetemperature responsive device and the means for releasing the biasedmember from the control of the heat responsive device extend. v

In order to permit the refrigerator controlling device to be readilyreplaced in case of failure, a sub-panel is mounted on the refrigeratorwith electrical connecting means provided thereon whereby when thecontrolling device is placed on the sub-panel, the proper electricalcircuits will be establishedto permit control of the refrigeratingapparatus by the controlling device. By sealing the cover on thecontrolling device tampering by unauthorized individuals is prevented.

In the drawing, Fig. 1 represents an exploded view of the cover,switch-mechanism, and subpanel to show their relation and cooperation;Fig. 2 is a plan view of the switch mechanism; Fig. 3 is a section, ofthe switch mechanism and subpanel; Fig. 4 shows the switch mechanismmounted upon a refrigerator; Fig. 5 shows the refrigerator circuit.

Referring to Fig. 2, the stationary contact 10 of the switch mechanismand the movable contact 11 cooperate to open and close a circuit throughthe refrigerator motor in response to the temperature-responsive device26. The elements 12 and 13 mechanically connecting the member carryingthe movable contact and lever 14, are the pivoted means and spring meansfor causing the snap action of the movable contact 11. Urging the switchmechanism .to the open position is the resilient means 15 in contactwith lever 14 and under compression. This resilient means determines thetemperatures at which the switch is opened and closed. In contact withthe other end of the resilient means is a lever 16 which is pivotallymounted at the point 1'7. A screw 18 is supported in a bracket 18' andmay be adjusted by means of the dial knob 19 to move the lever mechanism16 about its pivot to vary the compression of spring 15. This results ofthe switch mechanism since with a greater compression in the resilientmember, 15, a higher temperature is needed to cause the greater pressurein the sylphon bellows 26 necessary to overcome the compression in thespring member 15.

A screw means 11 is provided for rotating the member carrying thecontact 11 about its pivot 21'. Moving the contact 11 to the right hasthe effect of decreasing the temperature necessary to close the switchmechanism, since it will then be necessary for the pivoted end of theelement 12' to move a shorter distance to trip the switch than beforethe adjustment was made. Likewise, when the pivoted member 11 ispermitted to rotate in a counter-clockwise direction to move the contactfurther to the left when the screw means 11' is moved to the left, thepivoted element 12 must move a greater distance before the switchmechanism is closed, thereby increasing the temperature necessary toclose the switch mechanism. The shape of the lever mechanism 16 is forthe purpose of permitting the adjusting means to be mounted at'the endof the switch and to make room for the resistor 30.

It will be noted that by the special construction of the lever 16 forcompressing the spring 15, the adjusting knob may be mounted on the sideas shown. The shape of the lever provides space for the resistor 30,thus decreasing the space necessary for the apparatus. By making themember 22 perform two functions the number of parts is reduced, thusreducing the space necessary to mount the parts permitting a smallercontrol device unit. The result is a very compact unit with the controlsall on the the same side of the device and with fewer adjusting members.

It will thus be seen that I have provided numerous improvements in myautomatic switch mechanism including the means for making the variousadjustments thereon and for providing the necessary electricalconnections thereto.

The embodiment of the invention illustrated and described herein hasbeen selected for the purpose of clearly setting forth the principlesinvolved. It will be apparent, however, that the invention issusceptible of being modified to meet the different conditionsencountered in its use, and I, therefore, aim to cover by the appendedclaims all modifications within the true spirit and scope of myinvention.

What I claim as new and desire to secure by Letters Patent of the UnitedStates is: v

' 1. In combination, an electric refrigerator control device including abase, a motor controlling switch mechanism mounted on said base responesive to predetermined temperature and overload conditions to control arefrigerator motor, a motor controlling resistor mounted on said baseresponsive to overload conditions, motor controlling electro-responsivemeans on said base, said switch mechanism, resistor andelectro-responsive means being electrically interconnected to provide acontrolling circuit for a refrigerator motor, rigid contacts extendingthrough said base and electrically connected to said resistor, switchmechanism, and electro-responsive means, an independently mountedsub-panel carrying thereon resilient motor circuit contact memberselectrically connected to the refrigerator motor, said rigid contactsand resilient contact members being arranged in cooperating spacedrelation to provide quick detachable electrical connections for saidcontrol device.

2. A detachable electric refrigerator control device for a motor,comprising a base, a switch responsive to predetermined conditions foropening and closing a circuit through said motor, a resistor mounted onsaid base responsive to overload conditions of said motor, a relaymechanism on said base for changing he electrical connections to saidmotor, said switch, relay and resistor being electrically connected,rigid contact members extending through said base and electricallyconnected to said switch, resistor and relay, a sub-panel independentlymounted provided with resilient contact members cooperating with saidrigid contact members to provide quick detachable electrical connectionsfor said control device, and electrical conductors for connecting saidresilient members to the refrigerator motor.

3. A detachable control device for an electric motor-drivenrefrigerating-apparatus, having a hollow base, a plurality of motorcontrol members mounted on the top of said base and electricallyconnected to provide a control circuit for the motor, contact membersextending through said base into the hollow part thereof andelectrically connected to said motor control members, a sub-panelconnected to the motor and independently mount ed and provided withcontact members for coopcrating with said contact members on said baseto provide quick detachable electrical connections for said controldevice, said hollow base enclosing said sub-panel when said contactmembers are in contact with each other, said sub-panel permittinginstantreplacement of said control device by another control device.

4. A detachable control device for an electric motor drivenrefrigerating apparatus comprising a hollow base, a plurality of controlmembers mounted on said base and electrically connected to provide acontrol circuit for the motor, contact members extending from the sideof said base for connecting to a power supply, other contact membersextending through said base intgff the hollow portion thereof,electrical connections to-said first contact members and to said controlmembers, a sub-panel independently mounted and provided with contactmembers connected to the motor for cooperating with said contact membersextending through said base to provide quick detachable electricalconnections for said control device, said sub-panel fitting into thehollow of said base when said base is in operating position with thecontact members in engagement, said electrical connections providing acircuit from said power supply contacts to said sub-panel contactmembers when said sub-panel contact members and said contact members onsaid base are in engagement.

5. An apparatus provided with a chamber having an electric motortherein, a sub-panel permanently mounted on said apparatus and providedwith a plurality of contact-making members, said contact-making membersbeing provided with terminals, electrical conductors for connecting saidmotor and said contact members, a detachable control device comprising ahollow base, a plurality of motor-control elements mounted on said baseand electrically inter-connected, contact members extending through saidbase into the hollow part thereof and connected with said motor-controlelement s, said sub-panel contact members and said contact members onsaid base being in contact with each other to provide an electricalcontrolling circuit between said motor-control elements and said motorwhen said control device is placed in operating position with saidcontact members in engagement, said hollow base enclosing said sub-panelwhen said control device is in operating position whereby said contactmembers are concealed and protected from accidental contact.

6. In combination, a refrigerator having an electric motor therein foroperating the same, a sub-panel on said refrigerator, contact mem-- bersindividually mounted on said sub-panel and provided with terminals onsaid sub-panel, electrical conductors extending from said motor andconnected to the terminals of said contact members, a detachable controldevice including a hollow base and provided with contact members ex.tending from the side of said base into the hollow part thereof forconnecting to a power supply, automatic switch means and motor startingmeans provided with an overload device mounted on said base, said powersupply contact members, switch, starting device, and overload devicebeing electrically connected, contact members connected to said switch,starting device and overload device and extending through the base intothe hollow part thereof for cooperating with said resilient contactmembers when said base is in said base, said switch mechanism, resistor21 eleectroresponsive means being electrically int connected and rigidcontacts extendi. said base and electrically connected. sistor, switchmechanism, and elec means, an independentiy mounted rying thereonresilient motor circu bers, rigid contacts 1" members being arranged inrelation to provide ij-{llli' connections for said co 1 DEL n o It

